How can I adjust my Amazon EventBridge schedule for daylight saving?
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I’ve created an Amazon EventBridge rule that runs on a schedule and I would like to adjust the rule for Daylight Saving Time (DST).
Amazon EventBridge’s schedule rule runs in response to an event or at certain time intervals. For example, you can use a schedule rule to periodically run an AWS Lambda function. EventBridge allows you to create two types of schedule rules:
rules that run at a regular rate (these use a fixed-rate expression)
rules that run at specific times (these use a cron-based expression)
As a best practice, use the Amazon EventBridge Scheduler instead of an EventBridge rule to adjust the Daylight Saving Time. This is a serverless scheduler that allows you to create, run, and manage tasks from one central, managed service.
Currently, all scheduled event rules use the UTC+0 time zone, and the minimum precision for a schedule is one minute.
Amazon EventBridge Scheduler automatically adjusts your schedule for Daylight Saving Time. When the time shifts forward in Spring, your schedule invocation gets skipped if the cron expression falls on a non-existent date and time. When the time shifts back in the Fall, your schedule runs only once and doesn't repeat its invocation.
For example, in a rate-based schedule that uses days as the unit, days represents a 24-hour duration on the clock. When Daylight Saving Time shortens a day to 23 hours, or extends it to 25 hours, the EventBridge Scheduler evaluates the rate expression 24 hours after the schedule's last invocation.